Cowl plugs leash

A

asicer

Touchdown! Greaser!
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asicer
Over the prop hub? Under the prop hub? If a 3 bladed prop, in front of the blade of behind the blade?
 
asicer said:
Over the prop hub? Under the prop hub? If a 3 bladed prop, in front of the blade of behind the blade?
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Do it in a way that if you crank the engine, the blade will snag the leash and pull/fling the cowl plugs out.

Like this
Cessna172F_InletPlug.jpeg


or this:
cat-med_cowl_plugs.jpg


NOT like this:
CBA-CP1-2.jpg


NOT like this either:
xcowl_plug_front_3.jpg.pagespeed.gp+jp+jw+pj+js+rj+rp+rw+ri+cp+md.ic.29Blfhp6T-.jpg
 
I don't have a problem with placing the leash around the prop in that manner, but if you don't preflight the plane thoroughly enough to remember to remove the cowl plugs, you have other issues going on.

(How about the pitot cover?)
 
Sac Arrow said:
I don't have a problem with placing the leash around the prop in that manner, but if you don't preflight the plane thoroughly enough to remember to remove the cowl plugs, you have other issues going on.

(How about the pitot cover?)
Click to expand...

Everyone pilot (so far) is only human. That's why checklists themselves were invented. I see no harm in designing systems and methods to anticipate the possibility and more likely instances of human frailty. If one has forgotten to pull the cowl plugs, better to have to shut the engine down and go retrieve them than to start bubbling the cowl paint on climb out.

There is an old formula that holds the cost of some harm multiplied by the probability of that harm coming to pass should equal what you are willing to spend to avoid the harm. How much does it cost to drape the cowl plugs around the prop?
 
asicer said:
Over the prop hub? Under the prop hub? If a 3 bladed prop, in front of the blade of behind the blade?
Click to expand...

Over the hub, in front of a blade. The last thing you want is to get the cord wrapped around the crankshaft the one time you're in a little too much of a hurry.
 
Under the hub,behind the prop.
 
Under hub, behind prop.

Mine is a small rope that always gets hung up getting it off if I go over the hub and not long enough to go in front of the prop.

I also have the flags so it is more obvious from the cockpit of they are still in.

...my exhaust plug however, that has been left in but luckily blows right out on startup (just a taxi to fuel before you blast not doing a full and proper preflight)
 
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If you leave cowl plugs in for "just a taxi to fuel," you may overheat the engine. Particularly if you have some distance to go or there is a lot of ground traffic. It's worse than leaving cowl flaps closed because you get NO flow over the cylinders.

Flags have a tendency to fall off.

If it won't reach, it's better not to use cowl plugs at all. Unless your airplane sits for long periods, you won't get birds or other critters in there.

I've never used exhaust plugs on any aircraft and have yet to see a critter in there. Or in the cowling for that matter. I've found a few birds nests in the tailcone.
 
My mechanic just destroyed mine moving the airplane...says it starts fine with or with out them...
 
MAKG1 said:
I've never used exhaust plugs on any aircraft and have yet to see a critter in there.
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Somebody seriously needs to come up with a joke with a good punchline about a critter being blown out of the exhaust upon start-up. :D
 
MAKG1 said:
If it won't reach, it's better not to use cowl plugs at all. Unless your airplane sits for long periods, you won't get birds or other critters in there.

I've never used exhaust plugs on any aircraft and have yet to see a critter in there. Or in the cowling for that matter. I've found a few birds nests in the tailcone.
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Nest building is clearly seasonal and probably geo-specific, but I can tell you that when the stars are aligned just so, a pair of birds can start filling your cowling in no more time than you take for lunch. And given enough time, e.g. 2 days, they can stop you in your tracks...if you are lucky enough to see the nest before takeoff.

One day I flew my Maule into a NC beach strip for an overnight and a day of rides. When I walked up the plan I noted a small wren-like bird perched on my prop. Yep, there was the beginning of a nest. I cleaned it out of the Maule's overly large intakes and did my first ride. In the time it took to park it, run back to the beach house and return with new passengers the cowl had to be cleaned again - hot engine be damned. That was repeated 4 or 5 times that day. The bird was probably a Carolina Wren which is described as a "promiscuous nest builder" that builds several nests simultaneously before settling on one to drop eggs into.

Another day I flew the '10 up to NJ for a school reunion. It sat for 3 days and 2 nights without cowl plugs in place. My preflight showed an abnormal amount of bird droppings on the prop. I could see a few bits of grass but nothing serious. Then a bird flew right into my cowl with beak full of brush. I popped the top and found a whole bird condo in there. Turns out there's a lot more prime real estate on a 6 cyl engine and a lot more privacy with properly designed cowl inlets. I had no idea 1 or 2 birds could drop that much stuff under a cowl. It took several pairs of hands, a shop vac and a couple of hours to get things cleaned up enough to be safe for flight. It took another hour or two to get it all out once home. Amazing.

Now the cowl plugs go in 90% of the time and the pitot cover 100% of time.... did you know a bug can construct a blockage that only blocks ram air when flying through wet clouds? Perverse little buggers
 
MAKG1 said:
If you leave cowl plugs in for "just a taxi to fuel," you may overheat the engine.
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Exhaust plug....not the cowl plugs. Taxing with cowl plugs would be like boating with your fenders still out...AKA: Wally!

MAKG1 said:
What do Richard Gere and Shawn's airplane have in common?
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Well, there is a lot of electrical tape holding my plane together...so there is that!

Maybe I am just over protective...but I do not want any critters up ANY of my holes!

This is as bad as over/under toilet paper debate.
 
I leave my ropes on top usually... It is a bruces custom plug and has flags so it is highly unlikely i would start it without being removed...
 
MAKG1 said:
Over the hub, in front of a blade. The last thing you want is to get the cord wrapped around the crankshaft the one time you're in a little too much of a hurry.
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Put the cord in front of one blade. In manufacturing, we call that "poka yoke," the elimination of mistakes. You can forget to remove them, but you can't take off with them in place.
 
(How about the pitot cover?)[/QUOTE]

Damn Dude!
You gotta tie the pitot cover to the prop.
 
Never used them.

Control wheel lock and pitot cover on mine.

Prop tethers and control wheel lock at work.
 
Bill Watson said:
Nest building is clearly seasonal and probably geo-specific, but I can tell you that when the stars are aligned just so, a pair of birds can start filling your cowling in no more time than you take for lunch. ... I noted a small wren-like bird perched on my prop. Yep, there was the beginning of a nest. I cleaned it out of the Maule's overly large intakes and did my first ride. In the time it took to park it, run back to the beach house and return with new passengers the cowl had to be cleaned again - hot engine be damned. Amazing.

Now the cowl plugs go in 90% of the time and the pitot cover 100% of time....
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And just to think ---
There are varieties of birds (around here, including various Swifts and Sparrows) that are classified as protected species by Big Brother.

Removal of nests are federal offenses.
Yeah, better the plug than some do-gooder seeing you removing a nest and sicing the Fed on you.
 
If your aircraft is tied down , crimp an alligator clip such as is used for a battery charger on the end of the flag on your pitot cover. Clip it to the tie down rope and you will not forget to remove the cover. If you do , your wing is still tied down and you will not be going far.
 
I made my own from computer packing foam and ran two lines between. When I put it on I run one line on each side of the nose. I also put a coat hanger wire sticking up on the pilot side with a red flag on it
 
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